When taps are on full water goes cold
- Thread starter jaygips
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Combi?
That's what they do, especially in winter.
Run the tap slower.
If that doesn't help, use a thermometer to measure the actual cold and hot temperatures
And fill a bucket at the hot tap, time it, calculate litres per minute delivered, and post all three figures on here.
That's what they do, especially in winter.
Run the tap slower.
If that doesn't help, use a thermometer to measure the actual cold and hot temperatures
And fill a bucket at the hot tap, time it, calculate litres per minute delivered, and post all three figures on here.
There should be a flow regulator in the cold inlet so it should be limiting the flow to a given max, has that been altered/removed?
A 24 KW Combi is a waste of time they produce very poor HW
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When you say the water goes cold do you mean the boiler cuts out and the water goes freezing or it just isn't as warm as you expect?
in winter 24kw should produce plenty of hot water for one normal outlet at a time including a standard shower. In summer you could just about do two showers if they're reasonably water efficient and you don't like it steaming hot.
The only outlet ours can't handle on full is the bath tap as it's a high volume rather than water efficient tap, you have to turn it half way on if you want a decent temperature bath, but that's a rare event as we have a decent rainfall shower.
If you are expecting 12 litres a minute at 55c then you need to look elsewhere though.
in winter 24kw should produce plenty of hot water for one normal outlet at a time including a standard shower. In summer you could just about do two showers if they're reasonably water efficient and you don't like it steaming hot.
The only outlet ours can't handle on full is the bath tap as it's a high volume rather than water efficient tap, you have to turn it half way on if you want a decent temperature bath, but that's a rare event as we have a decent rainfall shower.
If you are expecting 12 litres a minute at 55c then you need to look elsewhere though.
There really should be a PRV on that supply then, basically though the boiler can only raise so much water per min by 35Deg, in winter the cold water can drop by as much as 15deg therefore the outlet HW temp of the boiler will drop by at least that much if the output flow is the same. As @JohnD suggest, drop the tap output or close the cold inlet to the boiler a bit to slow down the flow. It's just a normal headache of combi boilers in the winter, especially the lower powered ones.
Perfect example is a customer I went to yesterday complaining about low hot water flow, in the summer they get ~12L/min @ 50 deg, in the winter it has dropped to 6L/Min ~ 45deg and that's on a 35Kw Baxi. With 2 adults and 3 kids who are going into secondary school, the demand for hot water is pretty high. They are now cursing the last engineer that suggested putting in a combi early last year and getting rid of the system boiler and HW cylinder. We are now back looking at an unvented cylinder for them.
Perfect example is a customer I went to yesterday complaining about low hot water flow, in the summer they get ~12L/min @ 50 deg, in the winter it has dropped to 6L/Min ~ 45deg and that's on a 35Kw Baxi. With 2 adults and 3 kids who are going into secondary school, the demand for hot water is pretty high. They are now cursing the last engineer that suggested putting in a combi early last year and getting rid of the system boiler and HW cylinder. We are now back looking at an unvented cylinder for them.
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